Interlock system for elevator doors



Jan. 12 ,1926. 1569,454

r Fi. FQ BRUSH i INTBRLOQK SYSTEMFOR `ELEVA''OR .DOORS Filed Ain-11 11,l1923y f Patented Jan. l2, 1926.

UNITED STATES FREDERICK E. BRESIL-OE LOS ANGELES, CALIEORNIA, ASSIGNORTo ELEVA'IOR SAFETY APRLIANOECOMPANY, A cORPORATIONfoE CALIFORNIA. .Y

INTERLOCK SYSTEM FOR ELEVATOR DOORS.

Application filed yApril 11, 1923. Serial 110.331,381.

To aZ-Z whom z5l may concern.' l

Be it known that I, FREDERCKl F, BRUSH, a citizen'of the United States,residing `at Los Angeles, in the co-unty of Los Angeles and State VofCalifornia, have invented a new and useful Improvement Comprisingthe'lnterlock Systems for Elevator Doors, of which the following is aspecification;

vMy invention relates to elevators which are used to transport personsand loads from one ioor of a structure to another. It is common practiceto provide at each floora door sliding in said structure which may beopened to give access to the elevator when it is at that particularfloor.

The principal object of the inventionv is to provide means forpreventing the operation of the elevatorat any time except when all thedoors are entirely closed. `By thus preventing the operation of thekelevator when any door is open or partly open, the liability of anyperson beingkcaught and in jured by the moving elevator is reduced lto aminimum.` l y Further objects and advantages will be made evidenthereinafter.

Y Referring to the drawing, Fig. 1 is a side elevation partlyyin sectionshowing my invention. j y p Y Fig. 2 is a View from inside the car. Fig.3 is a plan view on an enlarged scale of the interlock mechanism at eachdoor. 'I

Fig. 4 is an elevation of same.

Fig. 5 is a section through oneform of elevator control switch.' l pFig. 6 is a section on a plane represented by the line 6 6 ofFig. 5.

In the form of my invention illustrated,

a building structurey is shown havingloors,` 11, 12, 13 and 14. Servingthese floors 'Isf an elevator car 15. At each floor a door 16 isprovided, this door having a ypin'l? on the top thereof. A crank shaft20'is provided at each'loor upon'which is secured a cam '21- so shapedas to be engaged and turned by the pin 17 as will hereinafter beexplained. Y

lRigidlyA secured to and turning with each of the camsv 21 is a crankl30 carrying a crank pin orv roller 31. This crank pin or roller 31contacts with an arm 40 which has al hooked endvtl, the arm 40' beingkeyed, or otherwise rigidlv secured, on a In'ain shaft 50. The mainshaft 50 extends to thefull height of the`l elevatorfshaft and Vturns ini Abearings 51,- carried on plates 52 which are each secured'by thebuildingV structure. Sef cured on the extreme lower end of the shaft 50is angelevator control switch y60A which consistsof; an insulatingYcasingl carrymg segments 62 vwhich may be conlnected by brushes 63which are mutuallyv connected and carried in an insulating member 64'.The switchf60 is connected in the elevator circuit either directlyorthrough suitable controllers being used to inhibit the operation ofthe mechanism operating the car 15. A thrust bearing 70 may be providedat the bottom ofthe yshaft 50 for taking all or a portion of the weightof the shaft 50. Secured onthe shaft 50 is a sheave, 80 operated bymeans'of a weightv 31 through a cable 82 which passes overan idlersheave 83. A spring or other equivalent device 'may be provided as asubstitute for the parts to 83, the purpose of which' is to' movetheshaft 5.0 in a negative or counter clock device dlrection as viewedin Fig. 3, to thr-ow the shaft 50 into whatmay be termed its normalposition unlessv this shaft is otherwise-restrained. The switch 60 is soarranged that ywhen the shaft 50 is inv its'normal `position'the"elevator circuit isV completed and the elevator may then bel y operated'through any suitable system 'of controlaWhen,however, thefshaft 5() hasbeen thrown vin a. positivefdirection from its normal position as shownin Fig. 3, the e1evator circuit is broken.y l p For the purpose ofthrowing the shaft'50 in a positivedirection, the'mechanismillustratedin Figs. 3 and`4 `is`used at each door.- The parts are shownin yfull lines in these figures in Vtheir normal positionl which is 'thepositionl they assume when all the doors are closed. It willv be notedthat the pin 17 is'`A inside the cam21 which is forked `to receive thispin. "When thefdoory starts tion against the pull of the weight 81. Thisis accomplished by virtue of the hooked end 41 of the arm 40 engagingthe roller 31, and the somewhat acute angle at which the crank 30 andthe arm 40 join, when eX- tended, as shown in the dotted line. A pull ofthe arm 40 toward the crank 30 tends to lock the two together, since thehooked end of the arm prevents the crank from slipping past. Themovement of the arm 40 opens the switch 60 and holds it open until sucha time as the door returns, the pin 17 then entering the cam 21 andthrowing the parts back into their normal position.

It will be noted that when any door is opened; the main shaft is rotatedto open the switch and that this switch will be held open until suchtime as that particular door is closed. It will therefore be seen that'to close the switch 60, it is essential that every door in the series beclosed practically to its full extent thus insuring the safety featureshown.

I claim as my invention:

h1. In an elevator: a structure having a plu-rality offloors; anelevator car serving said floors; a door at each floor closing anopening registering with said car when said .car is at said Hoor;mechanism for operating said car; a device which when open inhibits ,theoperation of said mechantisn; single vertical main shaft in saidstructure so connected to said device that a positive rotation of saidshaft from its no'rmal position will open said device; automatic meansoperated by a force independent of the movement of said doors forreturning said shaft to its normal position when said shaft is free fromexternal restraint; and a series of interlocks each operated by theinitial movement of its associated door to positively rotate said shaftand hold said shaft when so rotated until said door is substantiallyclosed.

2. In an elevator: a structure having a plurality of floors; `anelevator car serving said floors; a door at each fioor closing anopeningregistering with said car when said i car is at said floor;mechanism for operating said car; a 'device which when open inhibitsthey operation of said mechanism; a single vertical main shaft in saidstructurel so connected to said device that a positive rotation of-saidshaft from its normal position will open said device; automatic meansfor returningsaid shaft to its normal position when said shaft is freefromnexternal restraint; a crank shaft at each door; means which by apositive rotation of said crank shaft turns said main shaftin adirection opposed to the action of said returning means; and means bywhich the initial movement of said door so turns said.

crank shaft.

3. In an elevator: a structure having` a plurality of floors; anelevator car serving said floors; a door at each floor closing anopening registering with said car when said car is at said floor;mechanism for operating 'said ear; a device which when open inhibits theoperation of said mechanism; a

single vertical m'ain shaft in said structure so connected to saiddevice that a positive rotation of said shaft from its normal positionwill open said device; automatic means for returning said shaft to itsnormal position when said shaft is free from 'external restraint; acrank shaft at each door; a crank on each of said crank shafts; an armon said main shaft at eac-h door, each saidlarms (3o-operating with oneof said cranks toI positively rotate said main shaft and to hold itagainst the action of said automatic means when so rotated; and means bywhich each door so operates its crank shaft.

V4. In an elevatorl 1' a structure having a plurality of floors; anelevator car serving said floors; Ia door` at each floor' closing anopening registering with'said car' when said car is at said floor;mechanism for operating said car; a device which when openinhibits theoperation of said mechanism; a single vertical main shaft in saidstructure' so connected tosaid Idevice that a positive rotation of saidshaft from its normal p'osition will open said device; automatic meansfor returning said shaft to its normal position when said shaft iskfre'efrom eX- ternal restraint; a crank shaft atveach door; a crank on eachof said crank shafts; an varm on said main shaft at each door; each ofsaid arms co-operating with one of 'said4 cranks to positively rotatesaid mai-n shaft and to hold it against the action of said automaticmeans wheniso rotated; and means by which said crank shaft is sooperated by the opening of its door, being reversely operated by theclosingof said door.

5. In an elevator structure having a plurality of ioors; an elevator carserving said floors; a door at each floor closing an opening registeringwith Ysaid car when said car lis 'at said licor; mechanism for operatingsaid car; a device which when open inhibits the operation of saidmechanism; a single vertical main shaft in said structure so connectedtol said device that a positive rotationof said shaft from its normalposition will open said device; automatic means for returning said shaftto its normal position when said shaft isv free from external restraint;a crank shaft at each door; a crank on each of said crank shafts; an armon said main shaft at each door ;\V eachof said arms co-operating withone of said cranks to positively rotate said mainvshaft and to hold itagainst the action of said automatic meansv when so rotated; av cam se-lcured to 'each of said crank shafts; and

means by which each door operates its cam.

6. In a safety device for elevators,` Athe combination of: asubstantially vertical shaft; a control member operated through therotation of said shaft; a series of lever arms mounted along,r saidshaft in positions adjacent to elevator doors; `and means actuated bysaid doors` at the initial 'opening movement thereof, in a manner toexert a rotat-ive force against said lever arms so as 10 to rotate saidshaft, said arms being returnableto the position occupied beforerotation by a force independent of the movement of said doors.

In testimony whereof, I have hereunto set my hand at Los Angeles,California, this 5th day of April, 1923.

v FREDERICK F. BRUSH.

